Friday, June 15, 2012

You're a Vegetarian. Have You Lost Your Mind?

Hey, I'm back! Looks like when I don't blog new stuff, the archives get more reads, though, which is good. They ought to be useful for something, anyway. Lots of action on the Evolutionary Psychiatry front behind the scenes, some of it still super secret and all very exciting. AHS12 is coming up and with it reunions with a bunch of my best evo med-loving buddies, along with some new folks from far and wide. I've also been invited to talk to some more of my colleagues about the notion of "Evolutionary Psychiatry" and what it means. I'll let you know when I have that figured out.

It's a German study, and for a large population-based retrospective observational design, it's actually fairly thorough and sensible. And if you are a vegetarian, it certainly doesn't say that vegetarianism causes mental health problems. But in every single study except for two done in the past, vegetarianism has been linked with higher rates of depression, anxiety, and particularly eating disorders (bingeing, restricting, and purging behaviors). But to be perfectly honest, all those studies were pretty crappy (small, using special populations, and often based on just a few answers to general survey questions). I've reviewed a few of them. (My favorite has to be the one where they calculated arachidonic acid ingested to the hundredth of a gram based on data from a food frequency questionnaire. Hahah!) I don't think it is a coincidence that the two positive studies were done by the same group of researchers.

The interesting thing about the general trend that vegetarians aren't quite as mentally healthy as omnivores (in observational studies) is that vegetarians tend to do better in other measures of health. They are better educated, as a population they are generally younger, less likely to smoke or drink, more likely to exercise, and they tend to care about ethics and the quality of their food. However, vegetarians are also more likely to be female (which is more likely to be associated with anxiety, depression, and eating disorders by a long shot).

So this new study has some things to recommend it. For one thing, the mental health diagnoses were determined not by answers to typical questionnaires, but by a full clinical interview using psychologists or physicians, lasting an average of 65 minutes each. (Pretty impressive, considering there were over 4,000 participants in the population-based study). In addition, the researchers matched omnivores to vegetarians based on age, education, sex, and whether they were urban or rural and crunched those numbers as well, so we got a good sample that took out some of the major confounders that dogged the previous studies. Finally, this cohort was a purposeful random sampling of the German adult population (excluding people over 65, however), rather than the Seventh Day Adventists or adolescents and college students sampled in previous studies.

And when the researchers went down the line of depressive disorders, anxiety disorders, somatoform disorders (things like body dysmorphic disorder, health anxiety and hypochondriasis), and eating disorders, the mostly vegetarian were more likely to be afflicted, and the strict vegetarian even more likely.* The full blown eating disorder diagnoses were rare enough, however, that the researchers didn't compute the odds ratios, as they felt the dataset was not robust enough to be fair. Compared to the general population, the vegetarians were more likely to have mental disorders, and compared to the sex and education and population and age matched controls, the risk of mental disorders in vegetarians really shot up, with odds ratios hovering around 2, some as high as 3. (ORs around 2 is when you ought to start taking notice).

When the data was taken apart from another direction, it was found that participants in the study with depressive, anxiety, somatoform, and anxiety disorders consumed less meat than people without a mental disorder. The amount of vegetables, fruits, fish, and fast food did not have a consistent pattern separating those with and without mental disorders (except fish consumption was linked with reduced anxiety. Hmmm). In fact, unlike the 2010 Australian study, those with mental disorders in this German population were less likely to consume fast food than the mentally healthy population.

Temporally, the adoption of a vegetarian diet, on average, tended to follow the mental health diagnosis, suggesting that the vegetarian diet was not in fact causal. A retrospective study isn't the most robust way to determine this issue, but I would tend to believe this timing to be true, particularly for anxiety disorders, which often begin before the age of 10. The main exception to the temporal findings in this study were the eating disorders, which tended to start right around the same time as adoption of a vegetarian diet. As I've reported before, several of my eating disordered patients have told me they adopted vegetarianism so they would have an excuse to restrict food and not have to eat in public.

So what is going on? In Germany, are the neurotic perfectionists who are more likely to be choosey about food (and thus select vegetarianism and eschew fast food) also more vulnerable to depression and anxiety? Sure, could be. Or maybe those with mental troubles try to avoid what is thought to be bad food (meat and fast food). It is also possible that the nutrient deficiencies common in vegetarian diets (the most robustly studied being long chain omega 3 fatty acids and B12, though I think zinc and creatine and even too low a cholesterol could also be issues) could accelerate or worsen pre-existing mental conditions.

A large study comparing choosey, neurotic, perfectionistic omnivores (ahem) with strict vegetarians would be interesting, I think.

37 comments:

You have to appreciate the researchers that put this together- the mixed population and the care to match controls is impressive (thanks, you rigorous Germans!)

I don't think my year + of vegetarianism was particularly good for my mental health, though combined with the stress and sleep deprivation of submitting my first grant, writing my qualifying exam, and trying to please my mentors, perhaps some episodes of anxiety were inevitable.

Your comment about O3 made me look accusingly at the handful of walnuts I was working on... I feel compelled to take a shot of fish-oil now to balance the O6s. Walnuts and fish oil- talk about gross burps.

I have to say that much ofthe nutrition literature is absolutely awful (compared even to psychiatry, where it is actually something of a game to figure out how the pharmaceutical company biased the study… an insufficient treatment time here, an underdosed competitor drug there…). I wish all observational studies were this straighforward and honest!

Your last couple paragraphs are well put. This speaks to the multi-variable nature of...well...nature. What I would like to see is a population of vegetarians with these disorders along with other markers who were "converted" to omnivorism and what effect this change might have on their symptoms. And...what was considered an eating disorder? Orthorexia? I consider vegetarianism along with the SAD, eating disorders.

choosy, neurotic, perfectionist omnivores, ha. luv it. personally, I am convinced that only the mentally troubled would choose vegetarianism or veganism in the first place, so my only surprise is that the prevalence of mental health problems wasn't 100%. but then again, i'm biased, and according to many of my teaching evaluations, a jerk. plus, i like to drink a lot of wine which all the big experts tell me is bad for my muscle development and fat loss. (except Berkhan, of course, he loves the drinky). nice post Dr. Deans.

Seriously, "only the mentally troubled would choose vegetarianism or veganism in the first place"??! I'm convinced only the mentally challenged would knowingly choose eating something that is pumped full of growth hormones and antibiotics while wallowing in its own feces throughout its tightly confined life. Or drink its puss and blood laced excretion.

I chose a vegan diet because I don't think it is ethical to take the life and cause suffering to an innocent, sentient being.I am more healthy both mentally and physically than ever!!!

This study proves that consuming animal products is unhealthy: http://www.thechinastudy.com/

We claim to take animals seriously.We all agree that it is morally wrong to inflict‘unnecessary’ suffering or death on animals. Butwhat do we mean by this?

Whatever else it means, it must mean that it iswrong to inflict suffering or death on animalsmerely because we derive pleasure or amusementfrom doing so, or because it is convenient to do so,or because it is just plain habit.

But the overwhelming portion of our animal use—just about all of it—cannot be justified by anythingother than pleasure, amusement, convenience, orhabit.

I just love the differences (that may have been found) between the Australians and the Germans. Aussies: "I'm depressed. Eff it, I'm gonna get some take-away." Germans: "I'm depressed, so I will meticulously adjust my diet to try to make my life better." As I am from Texas, which honestly has a number of similarities with Australia (big and rough-hewn and lots of poisonous snakes and inhospitable areas and friendly folks wearing cowboy hats), these findings give me a little chuckle.

I have been to both Texas and Australia and loved both places. I never thought of them as similar, but you are right (thanks for the insight). Do you think poisonous animals make people friendly and rough-hewn? Or is that just a random n=2 correlation? :)

It's still just a correlation though, not causation, as you somewhat briefly mention in the last paragraph. There could be something else that is causing those mental health problems, and vegetarians just happen to be present in that category more. (I must point out that I'm an omnivore).

Some years ago there was a study about the number of hours of sleep per night and longevity. (link: http://health.ucsd.edu/news/2002/02_08_Kripke.html ). The data hinted that people who sleep 7 hours per night lived the longest. At this point, the researches suggested that sleeping 7 hours per night will increase you longevity, whereas anything more or less will decrease it. Now, although it has been conclusively proven that sleeping less than 6 hours per night can cause a range of health problems, there is nothing to suggest that sleeping 8 hours as opposed to 7 will CAUSE you to die sooner. It could just be that people in the 8 hours or more sleep per night group are the lazy ones and are less likely to exercise, and people in the 6 hours or less group, in addition to the health issues associated with less sleep, are more likely professionally busy people who don't have much time for exercise. From this perspective, the 7-hour group could just be the one getting the right amount of exercise, and THAT could be the cause, not the number of hours of sleep itself. If this is true, then it is possible for a person to sleep 8 or 9 hours per night AND exercise and still increase their longevity compared to the 7-hour sub-group who don't exercise. The only way to know whether sleep or exercise or some other factor causes longevity to increase/decrease is to consider all possible etiologies and divide your study groups based on these criteria to study their individual effects, such as dividing the 7-hour group, with a large enough sample of course, into those who exercise and those who don't and see if the data still holds true. Even then, though, it's still just a correlation, not the cause, and the only way this correlation can be identified as the cause is to find evidence for its mechanism of causation.

People with chronic anxiety are usually trying to find something to be anxious about, because why else would they be anxious? Surely the anxiety isn't just there (because one's brain is disordered). It's not surprising that some anxious people focus on diet and ethics and become vegetarians or vegans. Maybe such diets should be considered symptoms of anxiety disorders.

I disagree. In may case, the anxiety IS there already, without any apparent cause sometimes, or at least I have much more anxiety than lots of other persons in the same situation. Because I'm anxious I display anxious behavior. If I'm taking medication I don't (so much). I'm not very calm and then feel some need to find reasons to feel anxious (usually), specially because when I have High levels of anxiety (or depression for that matter) and out of medication my body will hurt. I'll be in physical pain. Why would I search for that? In chronic anxiety there is a problem in how the brain perceives reality and creates stress accordingly. The reasons for this could be so many. Environmental factors for sure but also biological factors. My mother is very anxious but she also has lots of digestive problems, inflammation and so on which indicate a damage intestinal flora, gut permeability issues, autoimmune issues, etc. Same with me. But don't think that people with chronic anxiety can do some reframing of the situations in their life and become a lot calmer. I tried that for years. It's not so simple. Chronic psychological problems are very difficult to change and are almost always a consequence of several factors but usually will power to change one's thinking is not enough. I wish it was. I would be cured. Maybe if I have some spiritual experience which makes me think I'm just consciousness and my body is not me (so I'm not afraid), than I'll be free of anxiety as some spiritual gurus do. I tried that also and couldn't believe it. I'm too skeptical...It's a shame. :)

And by the way, do you think that there is ONE psychiatrist in Portugal that can really help me besides using medication? Nope. And do you think that even though I made a lot of changes in my diet, social life, exercise, supplements it changed? Nope. Will I quit living a better life? Nope. Never! There's lots of things I haven't tried and even if I never feel really well I having a very deep sense of meaning (that I had to conquer) so even that won't break me. But please, don't tell me or anybody with a chronic psychological issue that they choose to have it! On the other hand I'm glad you can say that because it means that your reality is very far from this and that is a good sign. I happy that you have a happy and emotionaly stable core. And I know how difficult it is to put ourselves in the other person shoes when we can't find one experience we had that is even similar to what they are describing. But, if you can, try. Thanks :) Maybe Emily will came to Portugal and teach some doctors!

Actually, you agreed with what I said (my first two sentences were intended to be read with mild sarcasm, which doesn't come through well on the internet, especially if you are not a native English speaker). I was saying that the anxiety came first. Because many people don't understand that anxiety can be an independent problem, if they are anxious, they assume it is for a reason, and go looking for one. I did not mean that people go looking *for* anxiety. The reason I know this is that I have had similar problems, actually, not realizing that the problem was a disordered body, and I spent a lot of time trying to fix things externally to address the anxiety and depression. Those things didn't work.

And the spirituality aspect not working for your anxiety - that is further proof, in my opinion, that your anxiety has a physical cause, not a psychological one. The reframing you mentioned, the will power - as you implied, their lack of success all point to a biological cause.

I would never tell someone that they choose to have psychological problems - especially since I believe now that so many of them are rooted in poor lifestyle, particularly insufficient or harmful diets (which is why I follow this blog). I think most people would choose health if given the information they needed to make that decision.

HiSorry for the misunderstanding! In fact, it was to stupid to be true and I should have understood it! But, amazingly, some people think like that! Yes, think there's a BIG biological component to my anxiety! This blog is really important, in my opinion. Pedro Bastos is spreading the word in Portugal, organizing workshops, but there are still no doctors who are really sold to this idea. And he usually don't address psychological problems. I have to publicize this blog more I think!

Anxiety is often very very tough, usually because it strikes so young, and by the time someone seeks treatment, it has often been decades in the making. I've had some people who try all sorts of therapies and whatnot who finally decide to take meds, and respond wonderfully to a small dose of SSRI. Or the opposite happens, someone who never tried therapy (or no therapy specific for anxiety disorders) and is cranked up on tons of meds, then adds some anxiety reduction skills, and we are able to reduce or eliminate the meds. The most dramatic case I have of this second group is a man who was unable to work or leave his house except to see *me* (because presumably he could have a panic attack safely in my office) for two years, who began a very dedicated program of daily meditation. We were able to eliminate the meds (very slowly) and he's back at work and has been stable for about 4 years. Then there are folks for whom all treatments only work partially, and there are those who are unwilling or unable to do the meditation/mindfulness piece, or who do not want to give meds a try.

I would say anxiety is much trickier than a standard depressive disorder. More entrenched, often requires a a very aggressive and time-consuming approach. But for *most,* eventually, very treatable.

What about fecal transplant? Maybe could be a last resource option. I feel that in my case and in the case of my mother and sister, where anxiety is totally associated with digestive problems, inflammation, etc, it could help. I don't think probiotics and fermented foods are enough. Maybe a large large dose of probiotics?

This is entirely n=1, I realize, but going vegan after I had my daughter made me fatter and crazier. I already had PPD and it got much worse. And at some point my mental health stabilized, though. When I stopped to think about it I wondered what had changed, then realized I'd been deliberately eating more animal fat and coconut oil for the previous two or three years.

I'm still rock-solid stable compared to what I was in 2005 and I eat a meat-based diet now.

Just saying. We know B12 shortage damages mental health and that the wrong fats in the diet can affect brain function.

If I became anxious again niacinamide, 5HTP and a high-animal fat/ meat protein diet would be my first choices.The correlation between schizotypal behaviour, like subscribing to poorly-thought out conspiracy theories, and veganism, that might be a bit stronger than the anxiety-depression vege axis.Consider the moral torment of the "vegetarian". Whereas we find it natural to eat any animal we see for sale, they are constantly judging inferior species - mainly free range organic chickens - as unworthy of life.The Sophie's Choice involved in ethical shopping, with the repeated hangover of hypocrisy and failing to live up one's ideals, has got to be bad for the soul.

In fact, this was Germany - might not vegetarianism be a marker for liberal guilt?Whereas liberal guilt is not as strongly expressed in successful frontier societies like Australia or Texas (still enjoying possession of the fruits of past genocides).

A good take on the study. Researchers really need to start giving you more substance on vegetarians. First the "controlled trial" where they didn't even do a dietary analysis, and now this epidemiology that goes both ways with the confounders. Your brain is like fillet mignon and they're dumping ketchup onto it! I'll eat it but I've had better.

Anyway my current belief is that vegetarian diets are simply sub-optimal with regards to brain nutrition unless heavily supplemented. And it may not be the end of the world (except for chronic B12, choline and zinc deficiency on a poorly planned diet) but once someone already has anxiety or depression a vegetarian diet exacerbates it.

A small but significant correlation between vegetarianism and mental disorders - the small but significant trend towards non-conformity in vegetarians, increased stress factors, would explain it? Don't overlook the acute reality and the wide variety of coercive pressures that groups will apply to misfitting individuals/groups and the damage that can be inflicted. Vegetarians are more likely to belong to sections of society that are questioning of orthodoxy; artists, writers, activists etc and generally these types individuals live by different (more thoughtful perhaps) value systems, and so what with one thing and another.. tend to encounter varying levels disapproval, hostility that all to often accompanies this form of group dynamics?

I wonder if it is simply due to veg*ns having to see the animals they care about slaughtered and eaten every day, while also dealing with being a minority, that has an effect on their mental states. This would possibly help in explaining why these disorders come to the fore after the adoption of the diet. Thanks for the write up, I enjoyed it.

I was recently diagnosed as bipolar II. Right now my symptoms are the worst they've been in my life - and I absolutely can't stand the thought of meat. I just went back to a paleo diet from a conventional western grain-filled one, and held out over two weeks without touching a bite of animal before forcing myself to go back to paleo. Even now I have to muster up a tremendous amount of willpower to eat the stuff. It's not that I don't like it when I'm eating it, it's just an advance feeling of "ew, I REALLY don't like the thought/smell/sight of that," and it's really hard to overcome. Once I take the first bite I'm ok. But perhaps it's possible that certain mental disorders (and their related chemical imbalances) are in some part responsible for a revulsion to meat, and thus a switch to vegetarianism? I've always been an avid omnivore, aside from a brief period in my college days when I was stupidly convinced that vegetarianism was healthier (LMAO at that now!).

Kiki, I think that's a very interesting insight you're having. And I wish you luck with your recovery. I was a vegetarian for some time. And we recently had several different vegetarian houseguests, over a period of some weeks, where there was a lot more than just "not eating meat" going on (these are wonderful friends, but WOW - fussy eaters and even one who barely eats any vegetables... whom my husband refers to as a cake-a-tarian). I wish you luck with your diet and health, and speedy relief from your symptoms. I think your preferences can change, over time, as you respond to diet change. That definitely happened for me.

Vegetarian for 15 years here (with no plans to change, though I fully agree that a meatless diet is not what is natural for humans). There's always a lot of passion and controversy when it comes to diet, and I see both the omnivores and veg*ns do a lot of 'those idiots on the other side'. I do agree that vegetarians run the risk of several vitamin deficiencies that can affect mental health. Also agree that there is a correlation between neuroticism and finicky eating and fad diets, which in the 21st century translates into vegetarianism or veganism (I cringe when I see the eating disordered folks masquerading as 'vegan'). Anyway, not adding anything new here, but I just had to say this was a very well-written commentary on the article.

Should we really be surprised that a diet which restricts a main component of our ancestral diet should cause problems?

Some may be, but I'm sure not. On top of this, I know of far too many vegetarians who rely on too much processed food, thinking that just because it's vegetarian and (sometimes) low fat that it's going be 'healthy'. Anyone interested in the reasons paleo has become popular will appreciate the drawback of such an assumption. Just like the one people make about the 'organic' label. The fact that we can buy organic biscuits kinda blows the usefulnes of that label out of the water!

I'm 54 and have always had issues with anxiety and depression no matter what my diet was. I've never been vegetarian or vegan. These days I'm at about 75-25% "paleo" (or at least little grains, rice, corn, soy or sugars except in some fruit). I am a professional musician, have always done music or art and as a result don't get enough exercise. Nothing like touring 5-8 months out of the year to screw up a work out program! I have never done regular medication for my anxiety/depression though after 9/11 I did take something (can't remember now what it was) for the anxiety of dealing with TSA and having to ship my main instrument in the hold (it's almost impossible to "replace" a professional level musical instrument, especially a hurdy gurdy).

About 2005 I read about Emotional Freeing Technique and I've been using it ever since to deal with stage fright (gone) and a variety of other emotional and physical issues. It's worked remarkably well considering I've done most of it on my own. I'm now working with two professional therapists, both extensively trained in EFT and other "energetic" therapies including more standard training in psychotherapy. As I deal with the insanity of my family (childhood sexual abuse by my father, divorce, abusive neighbors and a sibling with aspects of Borderline Personality Disorder) including the loss of my mother (a year ago last August) and the resulting implosion of my family I am gradually getting my anxiety and depression properly under control for the first time in my life. I also credit an MD/ND/endocrinologist for finally properly diagnosing me with hypo-thyroid, low functioning adrenal glands and radically out of whack hormones.

Everything I've listed here in terms of changes in my diet, etc. made a difference to my anxiety/depression. But my mother's death and the stress leading up to it (aggressive, terminal breast cancer despite a life of great diet, exercise, healthy diet, great genes, etc.) including months of disturbed sleep and my sibling's abrupt escalation of mental issues, the loss of my home and several friends (including the executor of my mother's will) who chose to believe my sister's point of view of our relationship put me into a nose-dive that had me thinking about suicide on an almost daily basis. This all despite my great diet, loving partner/husband, lots of great, like-minded friends and a career I deeply enjoy,

I'm doing a lot better these days, still sticking to the "paleo" diet, getting more exercise due to a lull in traveling (yay, horses!) seeing the new therapist who is even more gifted at EFT than my regular one and getting some distance from the last three years. But it wasn't any one thing, it was a combination of stressors which honestly nearly killed me last winter, and it isn't any one thing bringing me back to health, either. My latest quest is to get enough O3 to help my body into more balance so as to deal with the little exercise I am getting in a more easy manner.

I'm not sure exactly why I'm posting this but here it is anyway. I've just found this blog through Mark's Daily Apple and I look forward very much to reading more here. Thanks for the opportunity to express myself and to read other's posts.

As I was reading this blog, I kept thinking about ALL the other interpretations besides nutrition CAUSING mental conditions--so it was nice to see you mentioned some at the end. I tend to be high in "neuroticism" in OCEAN/five-factor tests, and I could totally see that relating to my diet and separately to my anxiety issues; though I think the points from your last paragraph could ALL be correct.

I think I'm thoughtful and anxious about my food and everything (which leads to lots of, er, thought and anxiety), I'm choosy about my food because of my anxiety, yet I still have a pretty poor veg diet, and that exacerbates my anxiety/agoraphobia.

this is really interesting. I v had chronic pain for a while ( it s much better now, but i m tired emotionally and physically :( ). I started doing meditation seriously. in particular at night that i was in pain and i live by myself and i felt very lonely. Meditation helped me deal with pain ( i sometimes feel it has slowed me down too, or maybe pain and disability compared to before has done so, i don't know .. ). It certainly increased my physic capabilities. I can easily make people at ease and in peace now. Whoever comes to my place they say you and your place has such a energy that our energy decrease dramatically ( and they feel sleepy!!) ..

I believe as a result of meditation, i gradually started feeling less into having meat, still fish was okay. Within the past 4 months, i felt i cant take meat again( even fish that i used to love). Such a shame that I already have Iron deficiency. Also, i recently have a tendency to raw foods such as nuts, fruit, veggies, milk( i eat bread and egg as well. So I dont like cooked veggies.

I try not to loose weight because i m pretty fine ( for example i tend to eat 2-3 bananas each day that increase weight).. Besides, sometimes i feel i am going a bit extreme. Somewhere deep in my mind, i don't mind if i loose weight.

So i want to visit a doctor and see if this change is a good thing and has spiritual reasons due to meditation, or it is an eating disorder. Meanwhile, do you have any idea?

Read the FDA's new "increased suicide" warnings on SSRI's (What other deadly side effects will they discover?). I spent years on SSRI's, and they made me worse. My best cure has been a high-raw, plant based diet, as well as homeopathy and some supplementation.

I do eat free range eggs and dairy still. Strict vegans will do just fine with B12, Omega 3 (algae and flax) and Vitamin D supplementation (if adequate sunlight is not available).

The longest living Americans are vegetarians (7th Day Adventists). Hindus have also thrived on a vegetarian diet for centuries. President Bill Clinton promotes the China Study and is now on an almost 100% vegan diet. Mike Tyson went vegan and never felt better. :)

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About Me

Emily Deans, M.D.: I'm a psychiatrist in Massachusetts searching for evolutionary solutions to the general and mental health problems of the 21st century. Disclaimer: This information is for educational purposes only, and is in no way intended to be personal medical advice. Please ask your physician about any health guidelines seen in this blog, as everyone is different in his or her medical needs.